The short report has nothing to do with shorting stocks in the traditional sense. But it is a useful tool. It actually keeps track of sold, but not settled trades, which take three days to settle. Even if there is not a single shorted stock (traditional sense) there is a short report that tells how many trades have not yet settled. It is unfortunate that they named it as they did. It could have been called 'unsettled report' to be much less confusing.
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